Crime & Traffic

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DUI basics in Illinois

For purposes of Driving Under the Influence (DUI), "driving" means you just have to be in control of the car. For example, simply sitting in the driver's seat of the car may be considered to be in control of the car. To have control of the car, you must have the ability to start the car. Drivers have to follow the rules for driving restrictions. These restrictions have different age limits, procedures, and penalties.

The rules say that a person cannot:

  • Drive under the influence of drugs or alcohol
  • Drive while using a cell phone
  • Violate curfews
  • Drive a car with too many passengers in it

Driving under the influence of alcohol or drugs (DUI)

For people who are 21 years or older, the legal limit for blood alcohol content while driving is 0.08. People under 21 cannot have any alcohol in their blood while driving. Driving under the influence does not only mean driving under the influence of alcohol. You can be arrested for DUI if you are under the influence of any drug.

DUI is a Class A misdemeanor , punishable by up to one year in county jail and a maximum fine of $2,500 plus court costs . A DUI may become a felony (aggravated DUI) for various reasons, including:

  • Having three or more DUIs
  • Driving under the influence with a suspended or revoked license
  • Committing a DUI while driving without a valid license or permit
  • Causing great bodily harm, disfigurement, permanent disability , or death while committing a DUI
  • Driving without auto liability insurance while committing a DUI
  • Committing a DUI in a school zone and causing injury
  • Driving under the influence with a minor in the car, resulting in injury to the child
  • DUI with a minor in the car, resulting in injury to the child

Aggravated DUI can be punished by more than a year in jail.

What is a field sobriety test?

If you are stopped by the police, and the police suspect that you may be under the influence, the officer may conduct a field sobriety test.

A field sobriety test is a test where you are asked to touch your hand to your nose, stand on one leg stand, and walk along a straight line and turn. The officer will watch you do these things, and take notes, which they can then use in court to show that you were intoxicated. Illinois does not require you to take these tests, but if you refuse to take them and are found guilty of a DUI, you can face harsher penalties.

Underage drivers who are stopped and arrested for any traffic violation will be asked to submit to alcohol and drug testing. If you are found to have any amount of alcohol or drugs in your system, you will be subject to a 3 to 12 months suspension . If you refuse, the suspension will be 6 to 24 months.

How does a breathalyzer test work?

A breathalyzer test is done with a small device with a tube on it. The police officer will ask you to blow into the tube. The device will then show how much alcohol is in your blood. If your blood alcohol level is .08 or other drugs are found in your system, you will be subject to a statutory suspension of 6 to 12 months.

If you drive in Illinois, you agree to give a breathalyzer test when arrested for a DUI. This is known as an evidentiary breath test. You do not have the right to speak to a lawyer before testing, but you can refuse testing. Before administering a test, the police officer should advise you of the consequences of taking and failing or refusing the breath test. If you refuse to test, your license will be suspended. Your license will also be suspended if you take the test, and the test shows that your blood alcohol content is above the legal limit. The police officer may also request a blood or urine test.

Driving in Illinois does not mean you agree to a breathalyzer test when you have not been arrested for a DUI. If an officer offers you a breathalyzer test after pulling you over, this is known as a preliminary breath test, and is treated as a field sobriety test. A preliminary breath test may be rejected or taken without legal consequence to your license, but can give the officer cause to arrest you for a DUI.

Refusal of a preliminary breath test may not be used as evidence at trial against you. Refusal of an evidentiary breath test can be used against you in court. Prosecutors can argue that you refused because you knew you would fail. This is known as consciousness of guilt.

What are the driving suspension timeframes for DUI?

For persons 21 and older:

  • If you take the test but fail: 6 months suspension
    • If you have a valid driving license and are a first-time DUI offender, you may be able to drive with a Monitoring Device Driving Permit (MDDP) on the 31st day of the suspension. You also cannot get an MDDP if you caused death or serious bodily harm
    • The MDDP requires that you have a Breath Alcohol Ignition Interlock Device (BAIID) installed that lets you start your car only if you pass a breath test for alcohol. You may drive anywhere at any time once the BAIID is installed. You will have to pay the costs of the MDDP permit and the BAIID device.
  • If you refuse to take the test: 1 year suspension
    • If you refuse testing, which is your right, then the statutory suspension of your license will be longer, 12 to 36 months, depending on your number of DUI offenses. The suspension starts 45 days after you are given the notice of suspension.
  • If you failed the test and are not a first-time offender: 1 year suspension
    • You may be able to get a Restricted Driving Permit. If your license is valid, you will be allowed to drive for 45 days.
  • Second offense in 20 years: 5 years suspension
  • Third offense: 10 years suspension
  • Fourth offense: Lifetime suspension
    • You can ask can apply for a Restricted Driving Permit if requirements are met.

For persons under the age of 21, the statutory summary suspension lasts:

  • First offense: 2 years
  • Second offense: 5 years or until 21st birthday (whichever is longer)
  • Third offense: 10 years
  • Fourth offense: Lifetime

Getting a lawyer to represent you in a DUI case

The police officer who arrested you has to follow certain procedures and advise you of your statutory summary suspension rights. If these procedures are not followed, you can ask a judge to cancel your summary suspension. Talk to a lawyer if you think this applies to you. If you qualify, the judge will appoint a lawyer to represent you in court. You may also hire your private attorney or speak to the attorney assigned to the courthouse.

DUI student manual

The National Highway Traffic Safety Administration (NHTSA) shares this with students. This course is also given to police officers in the whole country. This helps one to understand, give, detect and document field sobriety tests. The new version is the Advanced Roadside Impaired Driving Enforcement (ARIDE) manual. This will help you learn how to have best practices to avoid a DWI. It also defines key terms. It then explains the ways officers should do these stops. 

Last full review by a subject matter expert
November 25, 2024
Last revised by staff
December 05, 2024